We're considering a sping getaway to St. John with our 1 year old. We enjoy hiking and are hoping to do some while there. Any suggestions for specific trails?

you should check out the book Off the Beaten Path Book of St. John. It has all the hiking trails listed, the difficulty levels and what you will see. There are several beaches on the island that require hikes to get to them. Which in my mind would make it worth it.
There are also guides that you can meet at the Nat. Park Center that will take you on hikes.
I have never been but have been researching STJ. myself for a trip in Oct.

thanks for the suggestion. I'll check it out.

jkurtiak, are you planning on camping at the park by any chance? I thought about it initially but we decided we wanted the comfort of a hotel since we have our baby.

Nope, we are honeymooning there. It looks like a great island with everything we are looking for. We are also going to spend a few days in nearby Virgin Gorda.
I have heard really great things from lots of different sources.
I have read the Fodors Guide to the Virgin Islands, The very best of the BVI, and Off the Beaten Path St. John. All have been very good. Especially the fodors guide...no plug intended. It was very clear and easy to read. They do have alot about the different accomodations as well, including ecoresorts and camping.
If you need any more help just ask. I am getting pretty close to feeling like my own guide book after all my research (i leave nothing to the imagination, I have to know it all before I get there)